Various groups around the world are working on the concept of PET/MRI imagers. They all use the enabling compact MRI-compatible solid-state technology in the PET detectors. The previous light sensor MRI-compatible technology implemented in the PET component was Avalanche Photo Diode (“APD”). A new whole body PET/MRI imager manufactured by mMR Siemens is using this technology. Most recently, research groups and companies are in the process of developing MRI-compatible PET systems based on the so-called Silicon Photomultiplier (“SiPM”) photo sensor. SiPMs have many designs and many companies and research centers around the world are developing and producing them. For example, Hamamatsu, Japan and SensL, Ireland are examples of a few such entities. In addition, a Korean group at Sogang University in Seoul and a Japanese group at National Institute of Radiological Sciences (“NIRS”), Chiba, Japan, are also developing SiPM-based PET rings for brain imaging inside MRI.
There is a dramatic need for hybrid PET/MRI imaging with MRI providing the anatomical structural information and PET-molecular information about biological activity of the relevant tissues and organs. The only currently practical method to produce combined PET and MRI images is to obtain separate PET and MRI scans, which are executed on separate scanners, at different time slots. A combination of images from these two modalities provides the most powerful diagnostic tool. Acquiring MRI and PET images separately and then co-registered them is a complicated and expensive two-part imaging process. The co-registration of these images obtained at different times may, in some cases, result in relevant correlation information being lost between the times the two scans were performed. The cost of these two expensive imaging procedures is also high and adds up in a particular patient case. Currently, PET/MRI scanners are just entering the market; however, these scanners are complicated and very expensive (approximately $6-million), making it prohibitive for medical centers to acquire them. Accordingly, they will have limited availability to most patients for many years to come. It is proposed herein to provide an alternative, low-cost system and method, mostly (but not only) applicable to imaging of a particular organ, such as, but not limited to, brain, breast, head/neck, prostate, OB/GYN, heart, and other extremities, by the inventive implementation of PET inserts in any MRI scanner.
The present disclosure is directed toward overcoming one or more of the above-identified problems.